Broad-winged Hawks on the Move

The breeding season is over. The days are getting shorter. The winds have changed, and raptors have begun their journey south. We are currently in the middle of peak Broad-winged Hawk migration, especially here in the Delaware Valley. Today over 10,000 Broad-wings were counted at Militia Hill Hawk Watch, in Fort Washington, Montgomery County, PA. Countless others have flown over other area hawk watches in the last few days.

Broad-winged Hawks breed in deciduous and mixed evergreen-deciduous forests across eastern and central northern North America, and into western Canada.  At the begining of September, Broad-wings herald the begining of fall raptor migration as they make their southbound journey – skirting the Great Lakes and coming down the Appalachian Mountains and Atlantic coast into the Delaware Valley.

During migration, Broad-wings can be seen riding the thermals or ‘kettling’ as it is known, in numbers ranging from a few to hundreds, as they move through our area primarily between Sept 15 and 23. Their journey continues further inland following a southwestly direction heading towards Texas.  By the time they reach Hazel Bazemore Hawk Watch, near Corpus Cristi, TX an estimated 95% of the Broad-winged Hawk population will fly over. Single day totals at Hazel Bazemore of 100-400,000 birds are possible during the last week of September.

Nearly all of the Broad-winged Hawk population overwinters from southern Mexico, through Central America and into South America, as far south as southern Brazil. To get there, they follow overland down the Gulf of Mexico and funnel through a narrow gap between the Sierra Madre Mountains and the Gulf in the state of Veracruz, Mexico. It is here that the greatest concentration of raptors can be seen. This is known as the “River of Raptors,” where one day counts around the end of September, beginning of October can number over 500,000 Broad-wings. All told about 1.7 million Broad-winged Hawks are tallied during this period – about 30% of all the raptors that pass through Veracruz in the fall – and we get to witness this extraordinary spectacle during our Veracruz “River of Raptors” tour.

Cape May Point, NJ and Hawk Mountain, PA are world renown North American locations for watching raptors in fall. A visit to either of these destinations or a hawk watch site closer to home is highly recommended.